Agriculture is a multi-billion dollar industry. Fertile soils are required for improved plant growth. In their absence, fertilizers are often utilized for agricultural crops. Air and water supply three important elements for plant growth, specifically carbon (C), hydrogen (H) and oxygen (O). When chlorophyll (green pigments) in plants is exposed to light in photosynthesis, these three elements are combined to form carbohydrates and release oxygen. Water is brought into the plant by root absorption from soil. Carbon dioxide (CO2) enters the plant through small leaf openings called stomata. The rate at which photosynthesis occurs is directly influenced by water and nutritional status of the plant, and is largely determined by the genetics of the plant.
Fifteen essential nutrients are supplied by soil. Of these, nitrogen (N), phosphorus (P) and potassium (K) are referred to as primary nutrients or macronutrients. This is because (1) they are required by the plant in large amounts relative to other nutrients, and (2) they are the nutrients most likely to be found in limiting supply when plant growth and development is impeded. Calcium (Ca), magnesium (Mg) and sulfur (S) are termed secondary nutrients, because their absence is less likely to constitute growth-limiting factors in soil. Zinc (Zn), chlorine (Cl), boron (B), molybdenum (Mo), copper (Cu), iron (Fe), manganese (Mn), cobalt (Co) and nickel (Ni) are termed micronutrients, because (1) they are found in only very small amounts relative to other plant nutrients in the average plant, and (2) they are least likely to be limiting plant growth and development in many soil systems
Fertilizers, particularly synthetic fertilizers have a major potential to pollute soil, water and air; in recent years, many efforts were done to minimize these problems by agricultural practices and the design of the new improved fertilizers. Conventional fertilizers are generally applied on the crops by either spraying or broadcasting. However, one of the major factors that decide the mode of application is the final concentration of the fertilizers reaching to the plant. In practical scenario, very less concentration (much below to minimum desired concentration) reaches to the targeted site due to leaching of chemicals, drift, runoff, evaporation, hydrolysis by soil moisture, and photolytic and microbial degradation. It has been estimated that around 40-70% of nitrogen, 80-90% of phosphorus, and 50-90% of potassium content of applied fertilizers are lost in the environment and could not reach the plant, which causes sustainable and economic losses.
In addition, plant pathogens, account for major economic losses in the agriculture industry. Moreover, global regulatory requirements are becoming more and more demanding with respect to the use of pesticides, particularly with respect to unmanaged or unnecessary pesticide residues. Thus, there exist mutually contradictory requirements of farmers to control destructive pathogens, which demands that more pesticide be used, while increasing pressures from regulatory agencies demand that less pesticide be used. These regulatory demands are aimed to protect the safety and health of agricultural workers and the general public. It is also well-known that the general public would like less chemical residue on fruits and vegetables. A particular consequence of this situation is that there is an increasing need to have more efficient methods of protecting plants from plant pathogens, especially economically important crops, fruits and vegetables.
The control of phytopathogenic fungi is of great economic importance since fungal growth on plants or on parts of plants inhibits production of foliage, fruit or seed, and the overall quality of a cultivated crop. Because of the vast economic ramifications of fungal propagation in agricultural and horticultural cultivations, a broad spectrum of fungicidal and fungistatic products have been developed for general and specific applications.
In view of the challenges and shortcomings in the art, there is a need for safe, environmental recyclable and user friendly compositions and methods for reducing the amounts of nutrients and fertilizers and for controlling plant pathogens, that are efficient and cost effective and will treat and provide better protection against phytopathogenic organisms.